This invention concerns the construction of interior trim pieces for covering air bag installations in the passenger compartment of vehicles. Currently, an air bag canister containing a stored folded air bag is mounted behind a region of a trim piece defining an opening through which the air bag deploys when inflated in response to a vehicle collision of a predetermined sensed severity. The inflating air bag forces open a covering door panel, which is hinged to an adjacent portion of the trim piece to allow opening the door panel and deployment of the air bag through the resulting opening.
The air bag deployment is quite forceful since it must be deployed with extreme rapidity in order to be properly in position to protect the occupant seated behind the air bag. Hence, powerful reaction forces are exerted on the air bag canister tending to move the same back away from the deployment door panel, resulting in slower opening of the door and delayed deployment of the air bag. The air bag canister thus must be held in position securely so that air bag deployment is not affected.
Also, for so-called invisible seam designs requiring severing of a skin layer, it is desirable that the trim piece regions adjacent the door panel be stabilized so that severing of the trim piece is not delayed by stretching of the trim piece structure under the pressure of the inflating air bag.
U.S. Pat. No. 5,522,616 issued on Jun. 4, 1996 and U.S. Pat. No. 5,393,088 issued on Oct. 5, 1993 describe the use of an anchored frame surrounding the deployment opening to solve this problem.
The door panel must resist the heavy impact of the air bag without fragmentation, and thus must be sturdily constructed of high grade, expensive materials, lest loose fragments be dangerously blasted into the passenger compartment.
Another problem that has been encountered is shifting of the door panel as it hinges open to a sufficient degree to allow impacting the windshield with sufficient force to fracture the same during an air bag deployment.
Construction of the trim piece to satisfy these potential problems tends to increase the cost to manufacture the trim piece.
It is the object of the present invention to provide a lower cost trim piece construction for stabilizing the deployment door panel and adjacent regions of the trim piece relative the air bag canister during air bag deployment, and for insuring that fragmentation of the door panel structure and/or impacting of the door panel against the windshield does not occur.